Acid-circulating system for mercerizing yarn



Oct. 20, 1925. 1,558,060

L. A. STEAD Filed Aug 1. 1924 Patented @et PATEN'l GFFME.

LAWRENCE A. STEAD, OF CHESTER, PENNSYLVANIA.

.ACID-CIRCULATING SYSTEM FOR MERCERIZING- YARN.

Application filed August l, 1924. Serial No. 729,446.

To all ifi/wm t may concern.'

lie it known that I. LAwnnNon Sinin, a citizen of the United States.residing at ihester. in the county of Delaware and State ofPennsjflvanizn have invented cert: in new and us .Lul improvements inAcit Circulating Systems for h'lercerizing ll'arin of which thefollowing is a specification.

My invention relates to an acid circulating system for mercerizing'arns. ln mercerizinpl yarns the yarn is immersed in a caustic solutionthen treated in an acid solution to neutralize` the caustic. To the bestresults the acid in the mercerizing vats must be maintained at apractically constant strength. eutralization reduces the strength of theacid and. as the work proceeds, more arid must he added from time totime. `tulphuric acid is generally used. The method heretofore in usehas been to test the strength of the acid solution in the vatsperiodically and add acid suflicient to increase the strength of thesolution in the vat to a point somewhat above that required. rl`he acidis added by hoisting a container above the vat and allow ing what issupposedto be a sutlicient quantity to flow into the vat. operation thevat is drained and the acid solution run to waste. Under this method thestrength of the acid is iirst of greater and then of less strength thanis required. 'Vhile a slight excess or deficiency of strength ispermissible, the tendency is to wide variations due to uncertainty ofcontrol, and no considerable degree of precision can be attained withthe most careful attention. The result tends to non-uniformity ofproduct. Moreover the waste of acid is considerable.

The objects of my invention are to provide an automatic system whichinsures a constant circulation of acid; which automatically maintainsthe acid in the mercerizing vats at a strength which insures propermercerization of the yarns; which avoids waste of acid, and whichdispenses with the skilled attention and much of the labor requiredunder the old method.

The drawing is a diagrammatic representation of mercerizing` apparatusembodying my invention.

The apparatus includes an acid storage tank l, designed to carry acid ofcommercial strength, a solenoid actuated acid feed-controlling valve 2,a mixing tank or well 3, a circulating pump 4, a mercerizing vat 5 andacid strength controlling mechanism 6.

After each days with the inercerizing vat by a pipe Yl() andk theinercerizing rat with the mixing tank by a pipe l1. An air pipe l2,designed for admission of air under pressure leads to the mixing tank.A. conductivity cell 1 3 is disposed in the mixing tank and iselectrically connected by leads lll and 15 with the strength controllingmechanism which is electrically connected by leads 16 and 17 with thefeed controlling valve.

The acid strength controllingmechanism and the feed controlling valveare preferably of the type disclosed in an application for acid strengthmaintaining apparatus filed of even date herewith by Frank H. Olden.

In operation, the deliver)v of strong acid from the storage tank throughthe feed controlling valve to the mixing tank is automaticallycontrolled by the conductivity cell and the strength controllingmechanism. The circulating pump maintains a. constant flow of acidsolution from the mixing tank to the mercerizing vat, and the overflowpipe is constantly returning a like quantity of the acid solution fromthe mercerizing vat to the mixing tank.

Under the old system the waste of acid usually amounted to 12% orthereabout. With my system none of the acid goes to waste. The oldmethod required constant and skilled attention. My system requires butincidental attention. Under the old method there was a serious lack ofuniformity in the product. With my system the product is practicallyuniform.

While I have described my invention as taking a particularform, it willbe understood that the various parts may be changed without departingfrom the spirit thereof, and hence I do not limit myself to the pre`cise construction set forth, but consider that I am at liberty to makesuch changes and alterations as fairly come within the scope of theappended claims.

Having thus `described my invention, what I claim as new and desire tosecure by Letters Patent is l. .An acid circulating system formercerizing including a storage tank; a solenoid actuatedfeed-controlling valve; a pipe leading; 'from the stnragv tank to thevulve: :i mixing;` tank; 1 pipe lending); 'from the vnive to the mixing;tank; n inerrerizing unit; n pump adapted to draw acid irf'nn tb@mixingv tank und deiivcr it io iba inercerixing unit; an ovm-finir; pipelending; from the inorcerizing uniii in rice mixing' tank; u lrndncfivity cell in tbv mixingaunk` und means, Controiied by neconductivity.' veli. Yfor ncinziting' the feeii-wiihoiiing valve.

Q. An acid Circulating System im' nim'- corizinp; invluding a' Storagetank: :i Snklnoid actuated eid-fontloi]ing' vniv: a pipo. lending; fromthe storage tank To the *unive whereby acid flows b v `gravit)v ifroniik@ Storage funk i0 the valvv; a mixing` tank: a

pipo lending irmn tba: miv@ to the niixingcr tank Whrabjv the :mid Howsbv 4giuivitv tu the mixing tank; a niriirixingg unit: n pump adapted toiii-im' :1L-iii sulution fumi the, mixing tank and deliver i1. in the:iwi-- cerizing unit; zn :wei-fion' pipe iznii w the inercerizing '.ini;no tb@ inix. whereby acid shinn Hows bj.' gravit): the inercerizing unitrn the mixing); tank: :1 conductivity wel] in tbc niiinfg funk. :indmeans` controlled by tbe Cfvnziuciivijc wil. Jfor animating; thvifmii-vfaitroiiing vulve.

n testimnnv Wirren? T have Signo@ nr.' nani@ i0 this Spe ifi atinii.

